Mounting for circuit breakers



Dec. 25, 1934. MALLQRY MOUNTING FOR CIRCUIT BREAKERS Filed Oct. 24, 1953Patented Dec. 25, 1934 UNITED STATES MOUNTING FOR CIRCUIT BREAKERSMarion Mallory, Detroit, Mich, assignor to The Mallory Research Company,Toledo, Ohio, a corporation of Delaware Application. October 24,

9 Claims.

This invention relates to a mounting for circuit breakers, such as areusedin ignition systems for automobile motors.

In the operation of automobiles, a great deal of ignition trouble hasresulted from the flashing, heating and fusing of the contact points ofthe circuit breaker, due largely to the creeping of the movable contactor to its rebound when the motor'isoperating at a comparatively highspeed.

30 The object of the present invention is to provide a constructionwhereby such creeping or rebound will be effectually prevented.

In carrying'outmy invention, therefore, provision is made for accuratelyguiding the free 15 end of the circuit breaker arm in its opening andclosingmovements, to insure perfect registration of the contactpointseven though the bearing for the lever arm may be loose or worn. Atthe same time, the spring which closes the contacts is so shaped andten-sio ned' as to interpose a slight frictional resistance to themovement of the lever arm, resulting in a snubbing action, whicheffectively prevents rebound of the arm and the movable contact carriedthereby.

The present specific embodiment of the invention will be moreparticularly described in connection with the accompanying drawing, inwhich,-

Fig. 1 is a plan view of one adaptation of the invention.

Fig. 2 is a front elevation thereof.

Fig. 3 is a perspective view of the circuit breaker and parts associatedtherewith.

Fig. 4 is a plan View of another adaptation of the invention.

Fig. 5 is a front elevation of the circuit breaker shown in Fig. 4.

Fig. 6 is a perspective view of the circuit breaker shown in Fig. 4.

As illustrated in the drawing, the invention is associated with anignition timer, which comprises a rotatable shaft 8 disposed centrallyof the shell 9. A circuit breaker cam 10 is secured to a sleeve 11 whichis adjustable circumferentially of the shaft 8 and on which the rotor 12is mounted.

In the adaptation shown in Figs. 1, 2 and 3, the stationary contactpoints 13 are mounted within the shell 9 and the movable contact points14 are secured to opposite branches of a spring 15. The central portionof the spring is secured to a lug 16 within the shell 9 and each branchof the spring passes about a circuit breaker arm 1'7 of insulatingmaterial which is pivotally mounted on a pin 18. The tension of thespring nor- 1933, Serial No. 695,037 (01. 200 30) mally maintains eachset of contact. points closed, except when they are opened by the actionof, the cam 10 against the opposite end of the circuit breaker arm 17.

As stated above, a great deal of trouble in the operation of ignitioncircuit breakers, as heretofore constructed, has been caused by thecreeping of the points, and this has been more apt to occur if thecircuit breaker arm is long and has a tight spring tension. The tendencyto creep, of course, is greatly increased if the pin 18 is slightlyunder size or the bushing worn.

In the present construction, however, the possibility of creeping issubstantially eliminated by providing an accurate guide for the freeends of the spring 15. This guide comprises a dielectric or insulatedspool 19 having flanges 20, between which the ends of the spring 15 arereceived, the distance between these flanges being substantially equalto the width of the spring, so that the only movement of the end portionor" the spring must be directly toward or away from the fixed contactpoint 14.

It is also to be noted that the upstanding flange of the lug 16, towhich the spring 15 is secured, is inclined inwardly, so that theattached central portion of the spring is warped, thereby causing adownward pressure of the free ends of the spring against the lowerflange 20 of the spool 19. This creates sufficient friction between thespring and the spool flange to effect a snubbing action which preventsrebound of the contact point 14 when it is closed by the cam 10.

In a four cylinder engine, the circuit breaker cam, of course, has onlyfour lobes, as shown in 10 in Fig. 5, and in many cases a singlestraight circuit breaker arm 17 is used. In adapting the invention tothis type of circuit breaker, the shape of the spring 15 is modified asillustrated in Figs. 4, 5 and 6, the other details of the inventionremaining the same as in the first described adaptation.

From the foregoing description, it will be apparent that my inventioneffectively prevents both creeping and chattering of the contact pointsof the circuit breaker, with a resultant elimination of the flashing,heating and pitting, which is a most frequent cause of faulty ignition.It is also obvious that the invention is not limited to the specificembodiments herein described, but is capable of adaptation, within thescope of the appended claims, to any type of circuit breaker which isused on automobiles of the present day.

What I claim is:

1. In a circuit breaker for ignition timers, a

fixed contact point, a pivoted circuit breaker arm with a cooperatingcontact point carried thereby, a cam for opening the contacts, a springfor closing them, said spring having a free end extending beyond thefree end of said arm, and means for accurately guiding the free end ofthe spring to prevent creeping of the movable contact point withreference to the fixed contact point.

2. In a circuit breaker for ignition timers, a fixed contact point, apivoted circuit breaker arm with a cooperating contact point carriedthereby,

a cam for opening the contacts, a spring for clos-' ing them, saidspring having a free end extending beyond the free end of said arm, andmeans for frictionally engaging the free end of the spring, therebyefiecting a snubbing action to prevent rebounding of the movable contactpoint.

3. In a circuit breaker for ignition timers, a fixed contact point, apivoted circuit breaker arm with a cooperating contact point carriedthereby, a cam for opening the contacts, a spring for closing them, saidspring having a free end extending beyond the free end of said arm, andmeans for accurately guiding the free end of the spring and at the sametime exerting a frictional resistance against it to prevent creeping orrebounding of the movable contact point.

4. In a circuit breaker for ignition timers, a pair of contact points, apivoted arm on which one of the contact points is carried, a cam foropening the contact points, a spring for closing them, and a guide forthe side edges of the spring, said spring being warped laterally so asto exert pressure against one side of the guide, thereby effecting asnubbing action which prevents rebounding when the contact points close.

5. In a circuit breaker for ignition timers, a pair of contact points, apivoted arm on which one of the contact points is carried, a cam foropening the contact points, a flat spring for closing them, and a guidehaving flanges between which the spring is accurately guided to preventcreeping of the contact points, said spring being warped so as to exertpressure against one of said flanges, thereby effecting a snubbingaction which prevents rebounding when the contact points close.

6. In a circuit breaker for ignition timers, a pair of contact points, apivoted arm on which one of the contact points is carried, a cam for.

opening the contact points, a flat spring for closing them, a lug towhich one end of the spring is secured, said spring extending about saidarm longitudinally thereof with its free end projecting beyond the same,and a spool having flanges between which the free end of the spring isguided to prevent creeping of the movable contact point with referenceto the fixed contact point.

7-. In a circuit breaker for ignition timers, a pair of contact points,a pivoted arm on which one of the contact points is carried, a cam foropening the contact points, a flat spring for closing them, a lug towhich one end of the spring is secured, said spring extending about saidarm longitudinally thereof with its free end projecting beyond the same,and a spool having flanges between which the free end of the spring isguided to prevent creeping of the movable contact point with referenceto the fixed contact point, the surface of the lug to which the springis secured being inclined to the axis of the pivoted arm, therebycausing the free end of the spring to exert pressure against one of saidflanges to effect a snubbing action which prevents rebounding when thecontact points close.

8. An ignition circuit breaker comprising a base, a rocker arm mountedon said base, an elongated spring extending about said rocker arm andfrom both ends thereof, means for fixedly anchoring one end of thespring to said base, and means on said base for slidably holding theother end of the spring for the purpose described.

9. An ignition circuit breaker comprising a base, a rocker arm mountedon said base, an elongated spring extending about said rocker arm andfrom both ends thereof, means for fixedly anchoring one end of thespring to said base, and means on said base for slidably holding theother end of the spring, the last mentioned means comprising a stop withtwo shoulders thereon, said spring being adapted to slide between saidshoulders.

MARION MALLORY.

